Components in power generation systems, such as the turbine rotor blades and the turbine stator blades, are used in turbine equipment and are often exposed to erosive environments. The erosive environment may result in component erosion caused by, for example, water droplets in steam turbines and/or by fine dust from oxide scale. In particular, water droplets can cause erosion of rear-stage turbine blades, where such water droplets are mixed with the steam for turbine driving. Erosion of turbine blades is problematic because it results in blade thinning and fatigue breakdown of the blade brought about by erosion.
One method of reducing erosion of the turbine blade from water droplets includes low heat-input build-up welding to build-up a plurality of single layers on the turbine component. Known build-up welding techniques take a significant amount of time to produce the desired erosion protection portion. Another problem with using such build-up techniques is that the erosion portion must also be machined after formation to the desired blade geometry, increasing processing steps and time in manufacturing, thereby increasing costs.
Another preventative measure is to use an erosion shield, for example, including a cobalt chromium alloy formulated for wear resistance (e.g. STELLITE®). The erosion shield is secured to the turbine component and protects the component from erosion. Materials for such erosion shields are provided in wrought condition, requiring processing and/or machining to achieve desired sizes and/or geometries. Such processing and/or machining is especially expensive for complex shapes, such as turbine blades or airfoils.
A process or producing or fabricating a shield, a process of fabricating an article having the shield, and an erosion shield that do not suffer from one or more of the above drawbacks would be desirable in the art.